Chess Board
[ECO code D15]
TRANSPOSITION
SLAV DEFENCE to SEMI-SLAV DEFENCE
White's QKt to QB3(c3) deterred 4..P-QKt4 by taking control of QKt5(b5), and contested K4(e4).
Black adopts the Semi-Slav main by a King's Pawn to K3(e6) quadrupling his QP support, although it blocks his QB and invites a 5.B-Kt5 pin. B-Alt.
    White  Black    Transp.White Black
 1. P-Q4   P-Q4		  (1.)
 2. P-QB4  P-QB3    (2.	P-QB4  P-K3  )
 3. Kt-KB3 Kt-B3    (3.	Kt-QB3 Kt-KB3)
 4. Kt-B3  P-K3	    (4.	Kt-B3  P-B3  )
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